How Finn became Fionna
by AnyaPanda
Summary: Finn has a new identity, and a new life looms before him. But there are obstacles that he must overcome,
1. Chapter 1

Chapter 1.

Finn had just revealed a long held secret to his brother, Jake. Finn wanted to become a girl and be called Fionna. Jake looked shocked, worried and confused. But when he opened his mouth, he said what Finn had hoped he would. "Well, uh, Fin-Fionna, I guess I have a sister now." Fionna smiled and hugged her brother tight. "Thank you thank you thank you!" she yelled. Jake returned the hug but remembered something else. "Listen, Fionna, I might be ok with this, this, whatever this is, but everyone might not be. I want you to know that whatever happens, you're still my sister. Okay?", he said. She thought for a moment on what he said. It was true; this was not new to her, but it was a new concept to the rest of the world as far as she knew. "Okay, Jake.", she told him.

After all this took place, Fionna went to bed and thought of who she should tell next. Marceline? PB? BMO? FP? She decided BMO should know next, and Marceline would know the next day. "Hey Bmo! I have to tell you something!" the little gaming device started toward Fionna. "Yes, what is it Finn?" "Well, that's the thing. It's Fionna now." The little robot was quiet for a bit, then said,"Oh, ok. I'll update your name now!"

The next morning, Fionna called Marceline and asked if she wanted to jam. Of course she did, she'd love to practice with him. On her way to Marcelines house, she wondered what the vampire queens reaction would be. **Glob I hope she'll still talk to me,** she thought. As she reached Marcelines house, she heard a bass thumping through the houses walls. **Huh, she started without me. Weird.** "Knockety knock! Marceline! I'm here!", she yelled to be heard over the music.

Inside she saw two people floating in the air and playing bass guitars. "Oh hey Finn, there you are. This is my cousin, Marshall Lee." Marceline said, gesturing towards the lanky, grey skinned boy. He flashed a peace sign at Fionna and she returned it with a smile. "Hey, Marcy? Can we talk for a second? In, like, private?" she asked rubbing her arm. Marceline cocked her eyebrow, but gestured towards the ladder leading towards her room. "Lead the way."

As Fionna climbed the ladder, her heart was beating hard and her thoughts were racing. When Marceline entered the room, she closed the little trapdoor behind her. "Okay, hero, what is it that you want to talk to me about?", She asked crossing her arms. "W-well, h-here's the thing, we-we're friends right? I can, like, trust you with things right?", Fionna asked nervously, cursing the way she stuttered. Now Marceline was worried. "Of course, what is it?"."Well, I'm, um, I'm a girl on the inside. Can-can you call me Fionna from now on?". She asked with her eyes closed.

Marceline was silent, but the Fionna felt arms wrapping around her. She opened her eyes to find Marceline holding her tight. "Of course I will, you big dork. Now come on, lets jam." Marceline let go and opened the trapdoor to find Marshall Lee floating lazily above the sofa. "Ready?", he asked, one eye open. "Yep, just had some stuff to clear up." Marceline replied.

Later that day, Fionna went to the Candy Kingdom to tell PB. She found the princess just beginning a new experiment. "Hey princess, can we talk for a sec?", Fionna asked . "Sure thing, just a second Finn.", Bubblegum told her. It had just occurred to Fionna how much hearing her old name bothered her. It was an intense dislike of it, almost hating it. "So, what's up?". "Well, um, I'm a girl on the inside and my name is Fionna and not Finn", she said in a rush, surprised it was getting easier to say. The princess blinked several times, and then squinted and said, "Well, okay, I guess. If that's how you feel, I suppose that's who you are then."

Fionna smiled wide and hugged the princess tight and ran off to tell more people. Who was next? Flame Princess, she supposed. She walked all the way to the Flame Kingdom, and found Flambo and asked for a flame shield. When she received one, she headed towards the palace.

"Hey FP, how are you?", she asked of the orange monarch. "Things are going well, how are you today?", the ruler replied. "I'm pretty well...Hey, can we talk in private? I need to tell you something." "I suppose so, whats up?", FP asked. "I'm a girl on the inside, and my new name is Fionna. Are we still friends?". Taken aback at this revelation, Flame Princess considered what she had just been told. "Of course, but may I ask what makes you think that?".

Finn considered the question for a brief moment. "Of course. First, the name Finn just sounds wrong to me. I feel fake, like I'm in someone else's body. It just doesn't feel _real_ , you know? Like, this isn't the real me." Flame Princess considered this for a moment before nodding in agreement; she could understand feeling fake.


	2. Chapter 2

Chapter 2.

Fionna went home, as the evening was closing in and the sun was setting. Jake was sitting at home with BMO playing Card Wars when Fionna walked through their treehouse door.

"Hey, Fionna..." Jake said, almost slipping up the name. His voice was concentrated, as most of his attention was given to the game. Fionna smiled to her friend.

"I told people, I told Marcy, Bubblegum and Flame Princess," she grinned. "They all said they'd call me Fionna!" Her voice was filled with excitement and the joy of acceptance.

Jake detached himself from the game. "That's awesome! I'm proud of you, Fi. That took guts,"

Fionna smiled, grateful for the fact that Jake had remembered her real name. "Thank you," she said, removing her hat. "And Jake?" She called, examining her blonde hair that just went past her ears.

"Yeah?"

"I think I'm going to grow out my hair again," she said, before exiting the room and heading up to bed. Jake nodded to her, silently saying goodnight.

Early in the morning, Fionna woke up, tired, but excited for the day. So far, everyone had been accepting and nice to her. She could only imagine the rest of the people on the list would be the same way. All she had left to tell were LSP, Simon, and Tree Trunks. She quietly dressed herself and went downstairs to eat something. Jake was still sound asleep.

Fionna left the treehouse, an eventful day ahead of her. First, she went to find LSP. Lumpy Space Princess had always been close to Fionna when she was Finn, and she could only imagine LSP would comply to her name and pronoun change. She spotted LSP in the forest with her friend Turtle Princess.

 **Why not tell them both at once?** Fionna thought. **They all have to know sometime.**

Her thoughts were interrupted when LSP called her over. "Finn! Come check out what we found!" She demanded.

"Actually, LSP, there was something I wanted to tell you. It should only take a few minutes," she was gaining confidence as she spoke.

"Okay, well what is it?" She asked.

"The thing is, I don't wanna be called Finn anymore. I wanna be called Fionna, and I want to be addressed as a girl,"

At first, LSP didn't say anything. Then, she spoke up. "What the lump? You're kidding, right?! Fionna? That's hilarious. Nice one, Finn, you almost had me,"

"No, LSP, and it's Fionna, not Finn,"

"That's so weird. Why? Is there something wrong with you? Honestly, Finn, I expected better. That's just disgusting. Come on, Turtle Princess. We're leaving. I don't wanna stay around this freak, or his freakiness might rub off on us," LSP and Turtle Princess left Fionna standing alone, wanting to cry.

She let out a sob, followed by a yell of anger. "Why would she say that?!" Fionna said, collapsing to her knees in the middle of the forest. She was silent for a while, thinking.

 **Maybe Simon won't be as bad. Maybe his acceptance will make up for LSP's. Maybe I can turn things around, and soon their perspectives will change.** She sat up, knowing what she had to do. Headed towards the Ice Kingdom, Fionna dried her tears and kept walking.

After a long trip, she arrived in front of the palace. The little penguins were standing around, and Fionna told them to retrieve Simon himself. They let her inside, where Simon was standing alone speaking to himself. "Finn the human! What do you want..?" He asked, a bit startled.

"Ice King, I'm only here to tell you that I don't want anyone to call me Finn anymore, it's Fionna now. I'm a girl," she held her breath.

"A girl?" More silence followed.

"Yes. A girl," Fionna swallowed hard.

"Get out,"

"What?"

"Leave my kingdom. I will not have this kind of monstrosity in my presence. If you don't leave right now, I will not hesitate to apply force," the anger in his face was evident. Fionna didn't waste any time running away from the Ice Kingdom.

Once again, her feelings were crushed. Why did she have to be treated so terribly because of how she truly felt on the inside? It wasn't fair. She needed some guidance from a motherly figure. Someone who would be there, and Fionna was sure she would accept her. She raced to Tree Trunk's cabin. Upon arrival, she knocked on the door. Tree Trunks herself answered, wearing her signature apron. The aroma of apple pie drifted past Fionna, and her stomach grumbled.

"Finn! Come on in, I've got a pie just fresh from the oven!" She said warmly.

"Thank you, I need some help," she said sadly.

"What's wrong?"

Fionna sighed. "I'm a girl on the inside. I've never felt comfortable as a boy, and I've been telling people my name is Fionna now. Yesterday, the three people I toled were very accepting and it made me happy. Now, the people I've been telling are being horrible to me. LSP thought it was a joke and laughed in my face. Ice King kicked me out of the Ice Kingdom. I'm just so upset right now..."

Tree Trunks let out a chuckle. Fionna looked surprised. "Finn, I know what you're feeling. I just want you to know that this will all blow over. Soon you'll forget about it and you'll be better again. It's a passing phase. You'll get over it,"

Fionna was shocked. She was slightly grateful that Tree Trunks hadn't kicked her out, but this wasn't much better. "It's not a phase, it's who I am!" She cried.

"Finn, why don't you take this pie home for you and Jake. Have a good night sleep, and think about this all over again. It's not really what you want,"

Fionna stood and left angrily. She didn't take the pie, and she slammed the door behind her. How could someone so nice say something so cruel?


	3. Chapter 3

Chapter 3

Fionna was running through the forest. She had been running since early evening, aimless in her navigation. The words of all she had told her most intimate secret spun round and round in her head. Tears leaked to the ground that sped behind her. **Why? Why do they hate me for being who I am?**

Unknown to her, a certain being floated in the air behind her. He had been following her for some time, noticing the tears that she left behind. **Hmmm, this could be interesting. Wait- isn't that-** "Finn?" he asked. She spun, turning to face him. "Marshall Lee?". The vampire grinned and said, "That's me. What're you doing out here so late?". She blushed and turned away from him. "You wouldn't understand Marshall. I don't even understand sometimes."

Marshall Lee raised his eyebrow. "Maybe if you told me, I could try to understand." He floated around to where she was facing so she had to look at him. She sighed. **Whatever, might as well.** "Marshall, I'm a girl, not a boy. I've lost friends for being me." She was almost crying as it all caught up to her. Marshall said nothing for a few moments, then reached up and started unbuttoning his shirt. He reveled something wrapped around his chest, it looked like a sports bra. "It's called a binder. It squeezes down breasts." He was half smiling at her.

"Not many people know. Marceline does, and now so do you, Fi- oh, uh, do you have a name picked out?" Fionna was smiling ear to ear while tears continued down her face. "Fionna. Marshall, I had no idea." He smiled again. "That's the idea girl. Hey, wanna go to a party with me?". The human grinned at the idea of spending time with the vampire. "Of course. What kind of party?"


End file.
